def test_no_integer(self):
m = ConcreteModel()
m.x = Var()
output = StringIO()
with LoggingIntercept(output, 'pyomo.contrib.preprocessing', logging.INFO):
xfrm('contrib.integer_to_binary').apply_to(m)
expected_message = "Model has no free integer variables."
self.assertIn(expected_message, output.getvalue())
def test_no_integer(self):
m = ConcreteModel()
m.x = Var()
output = StringIO()
with LoggingIntercept(output, 'pyomo.contrib.preprocessing',
logging.INFO):
xfrm('contrib.integer_to_binary').apply_to(m)
expected_message = "Model has no free integer variables."
self.assertIn(expected_message, output.getvalue())
def test_int_to_binary_negative(self):
m = ConcreteModel()
m.x = Var(domain=Integers, bounds=(-1, 1))
xfrm('contrib.integer_to_binary').apply_to(m)
reform_blk = m._int_to_binary_reform
self.assertEqual(len(reform_blk.int_var_set), 1)
reform_blk.new_binary_var[0, 0].value = 1
reform_blk.new_binary_var[0, 1].value = 0
m.x.value = 0
# Check that 0 == -1 + 1 * 2^0 + 0 * 2^1
self.assertEqual(
value(reform_blk.integer_to_binary_constraint[0].body), 0)
def test_int_to_binary(self):
m = ConcreteModel()
m.x = Var(domain=Integers, bounds=(0, 5))
output = StringIO()
with LoggingIntercept(output, 'pyomo.contrib.preprocessing', logging.INFO):
xfrm('contrib.integer_to_binary').apply_to(m)
self.assertIn("Reformulating integer variables using the base2 strategy.", output.getvalue())
reform_blk = m._int_to_binary_reform
self.assertEqual(len(reform_blk.int_var_set), 1)
reform_blk.new_binary_var[0, 0].value = 1
reform_blk.new_binary_var[0, 1].value = 0
reform_blk.new_binary_var[0, 2].value = 1
m.x.value = 5
self.assertEqual(value(reform_blk.integer_to_binary_constraint[0].body), 0)
def test_int_to_binary(self):
m = ConcreteModel()
m.x = Var(domain=Integers, bounds=(0, 5))
output = StringIO()
with LoggingIntercept(output, 'pyomo.contrib.preprocessing',
logging.INFO):
xfrm('contrib.integer_to_binary').apply_to(m)
self.assertIn(
"Reformulating integer variables using the base2 strategy.",
output.getvalue())
reform_blk = m._int_to_binary_reform
self.assertEqual(len(reform_blk.int_var_set), 1)
reform_blk.new_binary_var[0, 0].value = 1
reform_blk.new_binary_var[0, 1].value = 0
reform_blk.new_binary_var[0, 2].value = 1
m.x.value = 5
self.assertEqual(
value(reform_blk.integer_to_binary_constraint[0].body), 0)
def test_integer_var_unbounded(self):
m = ConcreteModel()
m.x = Var(domain=Integers)
with self.assertRaises(ValueError):
xfrm('contrib.integer_to_binary').apply_to(m)
def test_negative_integer(self):
m = ConcreteModel()
m.x = Var(domain=Integers, bounds=(-1, 1))
with self.assertRaises(ValueError):
xfrm('contrib.integer_to_binary').apply_to(m)
def test_integer_var_unbounded(self):
m = ConcreteModel()
m.x = Var(domain=Integers)
with self.assertRaises(ValueError):
xfrm('contrib.integer_to_binary').apply_to(m)
def test_negative_integer(self):
m = ConcreteModel()
m.x = Var(domain=Integers, bounds=(-1, 1))
with self.assertRaises(ValueError):
xfrm('contrib.integer_to_binary').apply_to(m)